#include <type_traits>
#include <iostream>
using namespace std;
class A{};
int main(){
  A a;
  cout<<boolalpha;
  cout<<"A  "<<is_object<A>::value<<"\n";//true
  cout<<"int  "<<is_object<int>::value<<"\n";//true
  cout<<"int&  "<<is_object<int&>::value<<"\n";//false
  cout<<"const int  "<<is_object<const int>::value<<"\n";//true
}
